#include <iostream>
using namespace std;
int main()
{
	int num,total;
	short int m,t,s,fin;
	cin>>m>>t>>s;
	for (num=1;total<s;num++)
	{
		total =t*num;
	}
	//cout<<total<<" "<<num<<endl;
	num =num-1;
	if (num>m) cout<<0<<endl;
	else
	{
		fin =m-num;
		cout<<fin<<endl;
	}
	return 0;
}
